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-rw-r--r--kernel/sched.c27
1 files changed, 19 insertions, 8 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index cca93cc0dd7d..08f86178aa34 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -57,6 +57,16 @@
#include <asm/unistd.h>
/*
+ * Scheduler clock - returns current time in nanosec units.
+ * This is default implementation.
+ * Architectures and sub-architectures can override this.
+ */
+unsigned long long __attribute__((weak)) sched_clock(void)
+{
+ return (unsigned long long)jiffies * (1000000000 / HZ);
+}
+
+/*
* Convert user-nice values [ -20 ... 0 ... 19 ]
* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
* and back.
@@ -2887,14 +2897,16 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
static void update_load(struct rq *this_rq)
{
unsigned long this_load;
- int i, scale;
+ unsigned int i, scale;
this_load = this_rq->raw_weighted_load;
/* Update our load: */
- for (i = 0, scale = 1; i < 3; i++, scale <<= 1) {
+ for (i = 0, scale = 1; i < 3; i++, scale += scale) {
unsigned long old_load, new_load;
+ /* scale is effectively 1 << i now, and >> i divides by scale */
+
old_load = this_rq->cpu_load[i];
new_load = this_load;
/*
@@ -2904,7 +2916,7 @@ static void update_load(struct rq *this_rq)
*/
if (new_load > old_load)
new_load += scale-1;
- this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) / scale;
+ this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) >> i;
}
}
@@ -4193,13 +4205,12 @@ static void __setscheduler(struct task_struct *p, int policy, int prio)
}
/**
- * sched_setscheduler - change the scheduling policy and/or RT priority of
- * a thread.
+ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
* @p: the task in question.
* @policy: new policy.
* @param: structure containing the new RT priority.
*
- * NOTE: the task may be already dead
+ * NOTE that the task may be already dead.
*/
int sched_setscheduler(struct task_struct *p, int policy,
struct sched_param *param)
@@ -4567,7 +4578,7 @@ asmlinkage long sys_sched_getaffinity(pid_t pid, unsigned int len,
/**
* sys_sched_yield - yield the current processor to other threads.
*
- * this function yields the current CPU by moving the calling thread
+ * This function yields the current CPU by moving the calling thread
* to the expired array. If there are no other threads running on this
* CPU then this function will return.
*/
@@ -4694,7 +4705,7 @@ EXPORT_SYMBOL(cond_resched_softirq);
/**
* yield - yield the current processor to other threads.
*
- * this is a shortcut for kernel-space yielding - it marks the
+ * This is a shortcut for kernel-space yielding - it marks the
* thread runnable and calls sys_sched_yield().
*/
void __sched yield(void)